1. Field of the Invention
The present invention relates to a method of automatically capturing a communication attribute converting apparatus in a switching apparatus for the purpose of automatically capturing and controlling the communication attributes of terminals in an information network when one or more terminals, have communication attributes that mutually differ and are defined as low-order layer data or high-order layer data, span a network or a plurality of networks, and to an apparatus using that method.
2. Description of Related Art
In recent years, accompanying a rise in the level of switching services for multimedia, there has been a strong demand for connections between terminals having differing communication attributes. It is necessary to meet this demand while making effective use of existing switching services, without making the operation complex and while providing a simpler system without a drop in switching system performance.
In the past, in networks made up of electronic switching exchanges which support the ISDN protocol, when communication is performed between terminals which have differing communication attributes defined as low-order layer data or high-order layer data, when the station containing the receiving terminal receives the call setting message (SETUP), a judgment is made with regard to the communication attributes of the calling terminal, which are contained in the low-order layer information elements and high-order layer information elements of that call setting message.
In the case in which the communication attributes of the calling terminal differ from those of the receiving terminal, if there is in the station containing the receiving terminal a communication attribute converting apparatus which can convert the communication attributes of the calling terminal to those of the receiving terminal, the communication attribute converting apparatus is captured and the call is received. If, however, there is no such communication attribute converting apparatus, "mismatched terminal attributes" is entered into the cause display of a disconnect message (DISC) and a request to disconnect is made.
If the user knows the communication attributes of the other terminal beforehand, it is possible for the user to dial a special number for the purpose of capturing a corresponding communication attribute converting apparatus, so that the station containing the calling terminal captures the communication attribute converting apparatus, enabling transmission to a terminal which has different communication attributes.
However, in the case in which there is no communication attribute converting apparatus in the station containing the receiving terminal, automatic connection of terminals having differing communication attributes is not performed, and even if the station containing the calling terminal has a communication attribute converting apparatus, because it is necessary for the user to verify the communication attributes of the other terminal before calling, systems in the past were deficient in terms of convenience and ease of use. This was a particularly large problem in multimedia networks, in which a wide variety of terminals are connected.